Manufacturer, Supplier & Exporter of ASTM A335 P9 Spool

ASTM A335 P9 spools are high-performance alloy steel tubes specifically designed for high-temperature and high-pressure service conditions. They are seamless pipes made from chromium-molybdenum steel, which contains roughly 8–10% chromium and 0.90–1.10% molybdenum. This composition provides excellent creep strength, oxidation resistance, and durability, making them suitable for critical applications in power plants, chemical processing, and petroleum industries..

The grade designation “P9” indicates a chromium-molybdenum alloy with specific mechanical and chemical properties defined under the ASTM A335 specification. It is widely recognized internationally and is compatible with ASME SA335 standards, ensuring it meets the stringent requirements for pressure piping used in high-temperature environments. The material is often chosen for applications involving superheated steam, thermal boilers, and heat exchangers..

Riddhi Siddhi Impex, a prominent supplier and manufacturer, plays a key role in distributing ASTM A335 P9 spools across India. They source high-quality P9 seamless tubes from certified mills and provide domestic availability in major industrial and commercial hubs. Their services cater to both small-scale fabricators and large EPC contractors, ensuring fast delivery and reliable product quality..

The chemical composition of ASTM A335 P9 spools is critical for its performance. Typically, the steel contains ≤0.15% carbon, 0.30–0.60% manganese, 0.90–1.10% molybdenum, 8–10% chromium, and trace amounts of phosphorus and sulfur (≤0.025%). These elements are carefully controlled during production to maintain high strength at elevated temperatures and prevent premature failure due to creep or scaling...

Mechanically, P9 spools exhibit excellent tensile and yield strength, with a minimum tensile strength of around 415 MPa and a minimum yield strength of 205 MPa. The pipes have good elongation properties, usually ≥30%, which makes them resistant to deformation under stress. The heat treatment process—normalizing and tempering—is performed to achieve the optimal balance of toughness, ductility, and creep resistance for long-term service in high-temperature environments..

ASTM A335 P9 Spools

Specification

Product Name	ASTM A335 P9 Spools
Manufacturer / Supplier	Riddhi Siddhi Impex
Base Material	Chromium-Molybdenum Alloy Steel
Form	Seamless Tube / Spool
Standard	ASTM A335 / ASME SA335
Size Range	12.7 mm to 914 mm OD
Wall Thickness	2.77 mm to 100 mm
Length	Random / Cut to Size
Pipe Ends	Plain End (PE) / Beveled End (BE)
Applications	Power Plants, Boilers, Heat Exchangers, High-Temperature Piping Systems

Chemical Composition

Element	Content (%)
Carbon (C)	0.05 – 0.12
Manganese (Mn)	0.30 – 0.60
Phosphorus (P)	≤0.025
Sulfur (S)	≤0.025
Chromium (Cr)	8.0 – 10.0
Molybdenum (Mo)	0.90 – 1.10
Nickel (Ni)	≤0.40

Mechanical Properties

Property	Value
Yield Strength	≥ 205 MPa
Tensile Strength	415 – 585 MPa
Elongation	≥ 30%
Impact Test	Optional, as per TR1 / TR2

Dimension Chart (Nominal)

Nominal Pipe Size (NB)	Outside Diameter (mm)	Wall Thickness (mm)	Length
12.7	12.7	2.77 – 6.35	Random / Cut to Size
50	50	3.91 – 7.11	Random / Cut to Size
114.3	114.3	6.02 – 12.7	Random / Cut to Size
273.1	273.1	9.27 – 25.4	Random / Cut to Size
406.4	406.4	12.7 – 32.0	Random / Cut to Size
914	914	25 – 100	Random / Cut to Size

Equivalent Grades

Standard	Equivalent Grade
ASME / ASTM	SA335 P9
DIN	1.7380 / 13CrMo44
EN	16Mo3
BS	1503-2 9Cr1Mo

Equivalent Standards

Standard	Description
ASTM A335 / ASME SA335	Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service
DIN 17175	Seamless Steel Tubes for Pressure Boilers
EN 10216-2	Seamless Steel Tubes for Pressure Purposes, Alloy Steel

Other Types of Alloy Steel Pipes

Type	Description
P1	Chromium-Molybdenum alloy steel for low-temperature service
P2	Moderate chromium-molybdenum alloy for high-pressure service
P5	High-temperature service alloy steel with 5% chromium
P11	11% Chromium alloy steel for high-temperature and pressure
P22	Chromium-Molybdenum alloy steel for power plant applications

Mechanically, P9 spools exhibit excellent tensile and yield strength, with a minimum tensile strength of around 415 MPa and a minimum yield strength of 205 MPa. The pipes have good elongation properties, usually ≥30%, which makes them resistant to deformation under stress. The heat treatment process—normalizing and tempering—is performed to achieve the optimal balance of toughness, ductility, and creep resistance for long-term service in high-temperature environments.

Frequently Asked Questions (FAQs)

Q1: What are the main applications of ASTM A335 P9 Spools?

A1: They are used in power plants, boilers, superheaters, heat exchangers, and other high-temperature industrial piping systems.

Q2: Can ASTM A335 P9 pipes be customized in size and length?

A2: Yes, Riddhi Siddhi Impex offers cut-to-size lengths and various diameters and wall thicknesses based on project requirements.

Q3: What is the chemical composition of P9 alloy steel?

A3: P9 contains 8–10% Chromium, 0.90–1.10% Molybdenum, ≤0.12% Carbon, and controlled amounts of Mn, Ni, P, and S.

Q4: Which Indian cities can get domestic supply of ASTM A335 P9 Spools?

A4: Domestic supply is available in cities like Mumbai, Delhi, Bengaluru, Hyderabad, Chennai, Kolkata, Pune, Ahmedabad, Surat, Vadodara, Nagpur, and more.